Multimedia Encyclopedia

Schirmer's test

How the Test is Performed

The health care provider will place a special paper strip inside the lower eyelid of each eye, under the eyelid (usually the bottom one). Both eyes are tested at the same time. Before the test, you will be given numbing eye drops to prevent your eyes from tearing due to irritation from the paper strips.

The exact procedure may vary. Most often, the eyes are closed for 5 minutes. Close your eyes gently. Closing the eyes tightly or rubbing the eyes during the test can cause abnormal test results.

After 5 minutes, the doctor removes the paper and measures how moist it is.

Sometimes the test is done without numbing drops to test for other types of tear problems.

The phenol red thread test is similar to the Schirmer's test, except that red strips of special thread are used instead of paper strips. Numbing drops are notneeded. The test takes 15 seconds.

How to Prepare for the Test

You will be asked to remove your contact lenses before the test.

How the Test Will Feel

Some people find that holding the paper against the eye is irritating or mildly uncomfortable. The numbing drops often sting at first.

Why the Test is Performed

This test is used when a person experiences very dry eyes or excessive watering of the eyes.

Normal Results

More than 10 mm of moisture on the filter paper after 5 minutes is a sign of normal tear production. Both eyes normally release the same amount of tears.

Vitamin A deficiency

Risks

There are no risks with this test.

Considerations

Do not rub the eyes for at least 30 minutes after the test. Leave contact lenses out for at least 2 hours after the test.

Even though the Schirmer's test has been available for more than 100 years, several studies show that it does not properly identify a large group of patients with dry eye. Newer and better tests are being developed. One test measures a molecule called lactoferrin. Patients with low tear production and dry eye have low levels of this molecule.

Another test measures tear osmolarity, or how concentrated the tears are. The higher the osmolarity, the more likely it is that you have dry eye.

Eye - illustration

The eye is the organ of sight, a nearly spherical hollow globe filled with fluids (humors). The outer layer or tunic (sclera, or white, and cornea) is fibrous and protective. The middle tunic layer (choroid, ciliary body and the iris) is vascular. The innermost layer (the retina) is nervous or sensory. The fluids in the eye are divided by the lens into the vitreous humor (behind the lens) and the aqueous humor (in front of the lens). The lens itself is flexible and suspended by ligaments which allow it to change shape to focus light on the retina, which is composed of sensory neurons.

Eye

illustration

Schirmer's test - illustration

Schirmer's test is used to determine whether the eye produces enough tears to keep it moist. The test is performed by placing filter paper inside the lower lid of the eye. After a few minutes, the paper is removed and tested for its moisture content. Fluorescein eye drops are also used to test if tears can flow through the lacrimal duct into the nose.

Schirmer's test

illustration

Eye - illustration

The eye is the organ of sight, a nearly spherical hollow globe filled with fluids (humors). The outer layer or tunic (sclera, or white, and cornea) is fibrous and protective. The middle tunic layer (choroid, ciliary body and the iris) is vascular. The innermost layer (the retina) is nervous or sensory. The fluids in the eye are divided by the lens into the vitreous humor (behind the lens) and the aqueous humor (in front of the lens). The lens itself is flexible and suspended by ligaments which allow it to change shape to focus light on the retina, which is composed of sensory neurons.

Eye

illustration

Schirmer's test - illustration

Schirmer's test is used to determine whether the eye produces enough tears to keep it moist. The test is performed by placing filter paper inside the lower lid of the eye. After a few minutes, the paper is removed and tested for its moisture content. Fluorescein eye drops are also used to test if tears can flow through the lacrimal duct into the nose.